Stony Brook RHIC Group Overview

1. Stony Brook RHIC Group Overview Barbara Jacak Stony Brook April 4, 2006

2. Today we’ll tell you about • Who we are & our role in PHENIX (Barbara) • Physics focus of the group • Past Achievements • Future Goals • Synergies between heavy ion & spin • And with Theory, Particle Physics and NSL • Spin Program at Stony Brook (Abhay) • PHENIX Upgrades activities (Axel) • Stony Brook graduate students’ work • Tour of our labs (Tom & Abhay)

3. Heavy Ion Physics Focus PAST Jet quenching via inclusive high pT charged hadrons in Au+Au, d+Au Thermal physics via identified hadron spectra in Au+Au Cronin effect (d+Au) Charm via single e± Thermal, charm e+e- pairs PRESENT Jet fragmentation fn. Away-jet modification Energy transport Baryon-jet correlation Charm E loss, via single e± to high pT Thermal g via conversions d+Au, AuAu e+e- pairs FUTURE jets as plasma probes multi-particle correlations energy dependence (+LHC) g-jet correlations Charm via displaced e± Thermal radiation, charm via low & intermediate mass e+e- pairs

4. Senior group members • Faculty • Axel Drees • Tom Hemmick • Barbara Jacak • Abhay Deshpande • Research Assistant Professor • Ralf Averbeck • Staff • Vlad Pantuev (Senior Scientist) • Richard Hutter (Technician) Research support DOE (group operations) NSF for Grid research HBD construction at SB

5. Postdoctoral Fellows • Alberica Toia • Justin Frantz

6. Heavy Ion Graduate Students Anne Sickles (PhD→BNL) Jamil Egdemir (PhD→Wake Forest U) Matt Nguyen Alan Dion Torsten Dahms Sarah Campbell Haijiang Gong Michael McCumber Harry Themann Jason Kamin Zvi Citron Bill Anderson (MSI) Summer 2006 Megan Juszkiewicz Matt Durham Nikki Cassano Spin students Kieran Boyle Rob Bennett Nathan Means Prasad Hegde

7. Physics accomplishments before 2005 Burward-Hoy Jia Purwar Matathias d Au Sickles

8. Centrality Dependence Au + Au Experiment d + Au Control thesis of J. Jia d+Au analysis by Jia & Anne Sickles • Dramatically different and opposite centrality evolution of AuAu experiment from dAu control. • Showed that jet suppression is clearly a final state effect!

9. heavy quarks and jet volcano at QM2005 ~ same energy loss for charm & light quarks  energy loss not all radiative also by collisions theses of J. Edgemir, Sergey Butsyk (run2) & Alan Dion (run4) Analysis and compilation by Mike McCumber

10. SB contribution to existing tools Drift Chamber RICH PMT array Tracking, Momentum Reconstruction in Central Arms Analysis Coordinator! 2006 Run Coordinator Upgrades Coordinator PWG Conveners

11. University Contributions to the Group • 2 New York State Positions • Pantuev, Frantz • collaborate with Rich Lefferts, Andrzej Lipski on HBD • Lab, clean room, assembly space • Benefit from Nuclear Structure Lab • Subsidized Electronics and Machine shops • $44/hour electronics, $37/hour machine • Matching funds for capital equipment • Drift Chamber FEE, HBD • Strong nuclear theory group (Brown, Shuryak, Zahed Wiedemann) + YITP (Sterman)

12. c g c g g g q q g q g q Spin synergy: Hard Probes for pp & AA • Most measurements planned for the future are based on hard scattering • Sensitive to gluon or spin structure of nucleons or the nucleus • Probe quark or nuclear matter ala “Rutherford experiment” or DIS • Basic processes utilized: • Parton-parton scattering: leading h or p0, angular correlations, jet production • Gluon-gluon fusion: open heavy flavor production, quarkonia • Quark-gluon Compton scattering: direct photons and g-jet central arms + VTX + HDB/TPC + NCC central arms + VTX central arms + VTX + HBD/TPC + NCC

13. dN/d(Df) 0 p/2 p p/2 p Df =+/-1.23=1.91,4.37 → cs ~ 0.33 (√0.33 in QGP, 0.2 in hadron gas) Example of synergy with theory • Mach cone? • Jets may travel faster than the speed of sound in the medium • Shock plasma by depositing energy via gluon radiation • QCD “sonic boom”

14. studies of strongly coupled plasma S. Ichimaru, Univ. of Tokyo

15. signal electron Cherenkov blobs e- partner positron needed for rejection e+ qpair opening angle Full scale prototype Hadron blind detector to reject Dalitz background  e+ e - po   e+ e - Toward Future Physics at RHIC GEANT model • Large acceptance displaced vertex detector • (Df ~ 2 p and |h| < 1), s < 100 mm D, B → e + hadrons (semi-leptonic decay) • |h|<1.2 • ~ 2p z 10 cm Strip Detectors (80 mm x 3 cm) at R ~ 10 & 14 cm Hybrid Pixel Detectors (50 mm x 425 mm) at R ~ 2.5 & 5 cm ~ 1 m

16. New Future Directions • eRHIC to study e + p and e + A (cold, dense gluonic matter) • More from Abhay on this • New faculty search to join ATLAS/heavy ion program Focus on jet modification Collaborate with USB particle physics group Mutual interest in jet reconst. and inner tracking First planning discussions w/ John Hobbs (USB) US-ATLAS HI collaboration

17. backups

18. what is a plasma? • 4th state of matter (after solid, liquid and gas) • a plasma is: • ionized gas which is macroscopically neutral • exhibits collective effects • interactions among charges of multiple particles • spreads charge out into characteristic (Debye) length, lD • multiple particles inside this length • they screen each other • plasma size > lD • “normal” plasmas are electromagnetic (e + ions) • quark-gluon plasma interacts via strong interaction • color forces rather than EM • exchanged particles: g instead of g

19. ideal gas or strongly coupled plasma? • Huge gluon density! • estimate G = <PE>/<KE> • using QCD coupling strength g • <PE>=g2/d d ~1/(41/3T) • <KE> ~ 3T • G ~ g2 (41/3T)/ 3T • g2 ~ 4-6 (value runs with T) for T=200 MeV plasma parameter G ~ 3  quark gluon plasma should be a strongly coupled plasma • As in warm, dense plasma at lower (but still high) T • other examples: dusty plasmas in space, cold atoms • such EM plasmas are known to behave as liquids! G > 1: strongly coupled, few particles inside Debye radius